Double suspended conductor system for electric railways



3 Sheets-Sheet 1'.

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0. J. VAN DEPOELE. DOUBLE SUSPENDED GONDUGTOR SYSTEM FOR ELECTRIC RAILWAYS.

Patented Aug. 13, 1889.

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DOUBLE SUSPENDED GONDUGTOR SYSTEM FOR ELECTRIC RAILWAYS.

E L E 0 P E D N. A V TU U Patented Aug lvi cnamo Charles .I Vmliepoele ydq 11 ,45%

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UNITED STATES PATENT OFFICE.

CHARLES J. VAN DEPOELE, OF LYNN, MASSACHUSETTS.

DOUBLE SUSPENDED CONDUCTOR SYSTEM FOR ELECTRlC RAILWAYS.

SPECIFICATION forming part of Letters Patent No. 409,156, dated August 13, 1889.

Application filed April 13, 1889. Serial N0.307,132. (N0 model.)

To all whom it may concern.-

Be it known that 1, CHARLES J. VAN DE- POELE, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Double Suspended Conductor Systems for Electric Railways, of which the following is a description, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon.

My invention relates to electric railways, and comprises a double suspended system of conductors, together with switches and crossing devices therefor, and means for making upward-pressure contact between the said double overhead lines of conductors and the vehicles carrying the motors and moving along the tracks of the railway.

The present system includes two workingconductors, each representing one side of the supply-circuit and suspended at a convenient height above the roadway.

For a line of electric railways having neither branches or switches the arrangement of conductors and contact devices would be, so far as the conductors are concerned, a mere matter of duplication, duplex contact devices, substantially as indicated in Letters Patent No. 394,038, being then sufficient for all purposes, and, as will appear, the connections between the stationary and moving parts of the contact devices, hereinafter referred to, and also set forth, described, and claimed in j a division of the present case, Serial No.

317,989, filed July 19, 1889, are an improvement upon my said former patent. Where, however, branches or turn-outs are required, complications are introduced, and specially designed and insulated apparatus is necessary to carry the current without leakage or short-circuiting between the adjacent conductors. Means for accomplishing this end are shown, described, and claimed in Letters Patent No. 394,039, granted to me December at, 1888, upon which those features of the present system are an improvement, not only in the means employed for insulating the respective conductors, but also in providing efficient methods for insulating the respective conductors where both positive and negative sides of the circuit are represented. According to the present invention the positive and negative suspended conductors may be arranged on either side of the track with respect to their polarities.

The details of the arrangement, construction, and operation of the several portions of my improved system will be hereinafter pointed out and referred to in the appended claims.

In the drawings, Figure 1 is an end elevation showing an arrangement of conductors embodying my invention as applied to a double-track railway. Fig. 2 is a plan view of a portion of the conductors of a doubletrackrailway arranged as in Fig. 1, and also provided with crossings and with a branch extending therefrom. Fig. 3 is a view similar to Fig. 1, but differing therefrom in the placing of the working-conductors with respect to their polarities. Fig. 4 is a plan View similar to Fig. 2, showing the conductors of a double-track-railway line arranged as in Fig. 3 and provided with crossings, and also with a set of branch conductors extending therefrom. Fig. 5 is a detail View showing one of the crossings seen in Fig. 4 011 an enlarged scale and in elevation. Fig. 6 is a plan view of what is shown in Fig. 5. Fig. 7 is a plan view on the same scale as Fig. 6, showing a switch or frog. Fig. Sis an enlarged view, in elevation, showing means for connecting and insulating the terminals of working-conductors of opposing polarities. Fig. 9 is an enlarged detail showing an alternative form of insulating-coimection between extremities of the working-conductors of different polarity. Fig. 10 is a View in elevation showing a form of insulatirig-connection for conductors of opposite polarity, and provided with means for protecting the insulation from the effect of arcs between the passing trolley and the extremities of the conductors, and also for protecting the surface or edge of the insulating-connection which is exposed to the passing trolley. Fig. 11 is an enlarged detail of a portion of the insulator seen in Fig. 10. Fi 12 is an elevation, partly in section, showing an insulator similar in most respects to that seen in Fig. 10,

- and also provided with the roof, omitted in previous figures. Fig. 13 is a view in elevation, partly broken away and in section, showing an insulator similar to that seen in Figs. 10 and 12, and differing therefrom only in the omission of the protecting devices on its lower edge. Fig. 14 is a view in elevation showing the arrangement of the tension and contact devices of the traveling connections by which the motor-circuits are connected with the suspended conductor. Fig. 15 is a plan view of the contact devices seen in the preceding figure.

As indicated in the drawings, the workingconductors may be suspended at a suitable height above the tracks of the railway between sets of oppositely-placed poles orother supports, the upper portions of which are seen at A A. .i

B (.l are respectively the positive and nega tive conductors above one line of tracks and D E of the other. The conductors B O D E are preferably sustained by some form of the arched suspenders shown in my patent, No. 393,317, suitable links, strips, or straps Z) of insulating material being interposed between the means for sustaining the positive con ductors B D and the wires (2 by which they are connected to the supports A A, and similar insulating devices 1) between the said positive conductors and the negative conductors O E. The said positive conductors may, however, be sustained by the insulated suspender, shown in my patent, No. 396,312, dated January 15, 1839. The precise method of insulating the said conductors is, however, immaterial, as is also the particular arrangement of supports, the poles A A being shown merely by way of illustration.

The negative conductors C E, while most thoroughly insulated from the adjacent positive conductors B D, are mechanicallyunited by wires D which are also advantageously employed as electrical connections between said negative conductors, thereby decreasing the resistance of the return-circuit. It will be apparent that by thus connecting the negative conductors in multiple are and utilizing the entire conductivity of both for either-line the said negative conductors may be of smaller cross-section individually, and yet possess the same conductivity as either of the positive conductors. A further advantage of this arrangement is found in the fact that both the outside conductors being of the same polarity-whether positive or negative is immaterial, since the positions of the said conductors maybe reversed with similar results-the tendency to leakage and loss of current through the earth is very much less than if the outside conductors were of opposite polarity. The latter plan, however, possesses certain advantages, and may be employed, as will appear.

In Fig. 2 is seen means for switching the contact devices in transferring cars from one track to another. The conductor D is provided with a frog (1, which may be of metal and in electrical connection with said positive conductor D. A branch conductor 1. extends between the frog (Z and an insulatinglink G, which link is secured to a metallic or other crossing F, attached to the negative conductor E, and the line of branch conductor 1 is continued by conductor 2, forming a continuation of conductor 1, and is in electrical connection with the crossing F. The conductor 2 extends to and is in electrical connection with a frog (1', through which it is connected with the negative conductor C of the other line. The negative conductor E is also provided with a frog 6, from which extends a conductor 3, which is insulated therefrom. The conductor 3 is mechanically connected to a crossing e, carried by the conductor O of the other line, and from the said crossing e a conductor 4, forming a continuation of the conductor 3, extends to a frog 6 carried by the positive conductor D. The conductor is insulated from the frog e and in electrical connection with the positive frog (1 through conductor 5. The branch conductors 3 at are both insulated from the negative crossing e, and are supplied with positive current through a conductor 6, spanning the crossing 6. 'With this arrangement it will be seen that contact devices upon the line D E, to be transferred in the direction of the arrow to conductors C D, will leave the conductors D E through frogs d 0, when they will simultaneously encounter the insulating links or sections G and be for the moment entirely deprived of current. The insulating-sections G are, however, of not more than a foot or so in length, and the momentum of the vehicle will carry the contact beyond the said insulated portions of the line,when one contact will pass to the branch conductor 1 and crossing F and the other to the branch conductor 3, which, as will be seen by the signs, are of reversed polarity. The positive current will then pass through the contact device previously in engagement with the negative conductor E and the negative supply-current through the con tact previously engaging the positive supply-conductor D. This, while reversing the direction of the flow of current in the motor-circuit, will not affect the forward movement, and the vehicle may be propelled along the branch conductors 2 3. As the said contacts approach the line 15 (J, the now positive contact will be deprived of its current while passing the negative cross ing 6; but, as in the previous instance, the momentum of the vehicle maybe such as will carry it past the said crossing, on emerging from which and passing the insulator G thereof it will again receive its positive current from the continuation a of the branch conductor, by which it is guided into the positive frog 6 The now negative contact simultaneously enters the negative frog (1, and in passing through the frogs d e the said contacts are carried or directed to the main conductors B O.

Where the above-described arrangement is employed to switch the contact devices from the main conductors D E to a branch or turnout, the branch conductors 2 3 will be replaced by the main conductors of the switch or turnout.

In Fig. 2 is also seen a crossing, by means of which a branch track can be carried from one set of main conductors across the other set and continued thence, as desired. For this purpose the arrangement of frogs, crossings, and branch conductors is the same for the main line D E;but the negative frog (1 is replaced by a crossingF, secured to the negative conductor and in electrical connection with the branch conductor 2. An insulating-link G connects the crossing F with a crossing F secured to the positive conductor B, but insulated from the crossing F, and also insulated from the continuation 7 of the said branch conductor.

Electrical continuity is established between the branch conductors 2 and 7 by a suitable insulated conduct-or 8, extending from the negative crossing F to the conductor 7. The positive branch 3 crosses the line B O in a similar manner, being connected by insulation with a crossing F desirably in electrical connection with the main conductor C, and connected by an insulating-link G with a crossing F attached to the positive conductor B. The continuing branch conductor 9 is in electrical connection with the positive crossing F and the conductor 3, extending between the negative frog E and crossing F is supplied with current from either or both of the positive main supply-conductors by insulated connections 5 and 10.

In Fig. 3 the alternative arrangement of main conductors is shown-that is, a positive and a negative or the reverse is arranged next adjacent to the supports A A. The central conductors are also of opposing polarity, and greater care will be necessary in the insulation of conductors so arranged. In addition to the insulating-connections b b, additional insulation 19 is inserted between the central conductors, and further precautions are taken to prevent leakage to the earth from the outside positive and negative conductors D O by insulators b interposed between the cross-wires b and the supporting-poles A A. The contact devices may be switched from one set of conductors to another, as indicated in Fig. at, where, as shown, a metallic frog H is attached to the negative conductor O, and connected by conductor 11 with insulatinglinks G, secured to the crossing h, which is in electrical connection with the positive conductor B. From the crossing 71 the negative branch conductor 11 extends to a frog H upon the negative conductor E. 30th portions of the negative branch conductor 11 are insulated from the crossing h; but both said portions may also receive current from the negative supply-conductors through their connection to the frog H II, or if it is desired to insulate the said conductors 11 from said frogs they should be connected by an insulatingconductor 12. The said insulated conductor 12 will, moreover, have the additional efiect of equalizing the pressure in the main conductors O E. The main positive conductor carries a frog H from which a conductor 13 extends to an insulating-connection attached to crossing h upon the negative-conductor E, and said conductor 13 is continued from the crossing 72/, to which it is attached by an insulated connection, and terminates at the positive frog II. As with the other branch conductor,both portions of the branch 13 may be electrically united by a connecting-c011 doctor 14, spanning the negative crossing h.

lVith an arrangement of main conductors in which the polarities are placed in alternation, the currents are not reversed in the traveling connection, the only interruption to the continuous flow of current therethrough being during the moment the positive trolley is passing the negative crossing 7L, and again when the negative trolley passes the positive crossing 71 here a branch extending from one set of main conductors crosses the other set, the negative frog II is replaced by a crossing I1 which is connected by an insulated section with a positive crossing II, from which the branch negative conductor 15 extends. Suitable electric connections are established between the conductors 11 and 15 by connection 16. The branch positive conductor 13 is carried across in a similar manner, being connected to but insulated from a negative crossing H, which is connected by insulated links G with a positive crossing H The branch conductor 17 is in electrical connection with the positive crossing Il The positive conductors B D may be further connected through the conductor 18, extending from the crossing H to the branch conductor 13.

An insulated crossing is indicated in elevation and in plan in Figs. 5 and 6, in which 6 is a metallic contact-plate, against the under side of which the trolley-wheel I presses in passing, being guided, when desired, by a central extension t. Side plates or flanges may also be provided to prevent lateral displacement of the trolley. The crossing is used either for positive or negative conductors, but is described in connection with the main positive conductor Ii, which may be secured to the said crossing -plate in any desired manner, although I prefer not to cut the said conductor, but to carry it over the top of the crossing.- plate, which, when so arranged, is provided at each end with guiding or depressing ribs 2' which engage the groove in the trolley I, and by which it is guided to the under side of the crossing-plate, and at the same time gradually depressed to prevent its being bounced downward by any sudden deflection, whichwould rupture the circuit and cause destructive sparking, substantially as set forth in Letters Patent No. 397,451, granted to me February 5, 1889. The conductor B crosses the switch-plate at the desired angle, to which of course the ribs 17-, extending under the extremities of said plate, also conform. Projections or lugs ff are secured or formed upon the plate 6 in positions conforming to the direction of the branch 11 from the negative conductor 0, as seen in Fig. I. To each of the said projections is secured a link of insulating material G, the specific construction of which will be hereinafter referred to.

To the extremities of the insulators G are attached the extremities of the said branchconductor 11, which is thereby insulated from the crossing-plate which is in electrical connection with the positive conductor B. The two portions of the branch 11 are electrically united by an insulated conductor 12, which is carried over the crossing-plate in any convenient manner.

The frog at e in Fig. 2, and shown on an enlarged scale in Fig. 7, substantially similar to the device described and claimed in my said patent, No. 397,4.51, an insulator Gbeing provided for the terminal of the branch eonduetor of opposite polarity. The insulators Gare each provided with a roof to prevent short-eircuiting the conductors of opposite polarity attached to their extremities, as would be the case if they became covered with water.

In Fig. 8 is shown an insulator designed to possess the tensile strength necessary to support a heavy conductor attached thereto, and the said insulator is formed with a metallic core in the form of a link J, which is coated with any good insulating material. One end of the insulator is securely attached to a tapering ear j, which is grooved upon its under side to receive the conductor and formed with an upwardly-extending aperture j, within which the extremity of the conductor is inserted and secured by bending over its free end 3'. The portion of the conductor in the groove on the under side of the ear j is permanently secured therein by soldering or other means. The opposite end of the insulator G is firmly attached to the projection extending from the crossing or switch in connection with which it is employed, such an attachment being indicated at f in Figs. 5 and 6, and the projection f is formed or provided witha continuation f extending under the switch-plate and acting to guide the trolley in the desired direction, as explained with reference to the ribs The lower edge of the insulator G forms a continuation of the path of the contact device between the rib f and the conductor attached to the ear j. Furthermore, the in sulaior should be so formed that when the insulating material upon one of its edges is worn or damaged it can be reversed in posi' tion. A slightly-dilferent form is seen in Fig. 9, comprising two insulated rods J J the ends of which are made fiat and extended to ailord a strong and well-insulated hold for connection to the earj and to the lug or projection This form is also reversible.

In Figs. 10 and 11 is seen an insulatinglink G, which may be l'e-enforced, as indicated in Fig. 8, or be formed of a heavy strip of strong insulating material. A trolley passing from a conductor of one polarity to the said insulator G will in many instances draw an are as it leaves the conductor, which are would under ordinary circumstances eat away the insulating material at or near its extremities. In order to prevent this, I form a number of serrations or notches K upon the lower edge of the insulator G, theserrations K being of such a width as would serve to stop the further progress of any are which might form between the trolley-wheel and the conductor it had just left. The notches K are indicated in Figs. 10, 11, and 12; but in Figs. 10 and 11 I provide afurther protection for the lower edge g of the insulating-link by insertil'ig a closely-arranged series of metal pins therein. The metal pins 7: are desirably provided with heads, and may be in the form of copper rivets, the shanks of which are inserted in holes bored along the lower edge of the insulator, the heads of the rivets being then pressed down to form a smooth but discontinuous metallic facing along the lower edge 9 of the insulator. \Vith this arrangement an arc would jump from pin to pin and gradually lose its force and become extinguished, the serrations K being sullicient in width and number to prevent its following the trolley across the insulator. The said insulator may, however, be used without the provisions just referred to, as indicated in Figs. 8, 9, and 13.

Each insulator is provided with a hood or cap K, desirably of insulating material, as wood or vulcanized fiber; but they may also be constructed of sheet-iron or other metal provided with a coating of durable insulating paint, cement, or enamel, and said roofs K may be attached to the insulators by sup ports is, secured thereto.

Duplex contact devices for making connection between the overhead conductors and the traveling vehicle are illustrated in Figs. 11- and 15. The mechanical construction of said contact devices includes arms L M, provided at their outer extremities with grooved contactwheels I O, rotatably mounted between the prongs o'f forks Z Z. The forks ll should be of conducting material, and may be provided with contact devices and frictionreducing bearings, substantially as shown, describerhand claimed in an application filed by me April 2, 1889, Serial No. 305,728. The contact-carrying arms I; M are journaled at or near the extremities of a rod on, which is centrally supported within a metallic block Q. The block Q is provided with a downwardly-exte1ulin g pivot passing through and rotatable in a metallic base-plate q. The extremities of the arms L M are held upwardly ICC IIO

against conductors B C by springs Rr, which are coiled about the portions of the rod m between the central support Q and the bases of the arms L M.

The arms L M might of course be placed near together upon the rods m, and the springs R 4" upon the outer extremities of the said rod; but the arrangement here shown is desirable, for the reason that the arms L M would then be separated, as are the positive and negative working-conductors,which separation would materially aid in securing ef fective insulation. The outer extremities of the springs R r are attached, respectively, to the arms L M, their inner extremities being attached to ratchet-disks S S, the serrated faces of which engage like serrations upon the lateral surfaces of the central support Q, against which they hear.

The serrations, indentations, or detent devices upon the surfaces S S and upon the support Q should be of such nature thatthey will move relatively to each other in one direction, and therefore can readilybe adjusted from one direction, so that by detaching the trolleys from their conductors and moving the arms rearward-that is to say, toward positions the reverse of those in which they are intended to operate-the tension-springs R '1' would be slackened until, all tension having been released, the tendency to coil the springs in the opposite direction would cause them to turn the ratchet-disks S S rearward anumber of notches, depending upon the distance to which the arms were moved and the previous tension of the said springs.

It will be apparent that the parts should be so proportioned that when the arms are turned into their extreme reverse positions, and then brought forward to their normal working position, the range of movement will be sufficient to impart the desired tension to the springs R r, the said springs R 4" having by such rearward movement been automatically locked at their inner ends to stationary detents when the arms were in reverse position. With such an arrangement no loosenin g or unloosening or adjustment of the parts is necessary, and neither keys nor wrenches are required, although, of course, the degree of tension which can be applied to the arm is limited to what under ordinary circumstances is found to be amply sufficient.

NVhile I have described the parts S S as ratchet-disks, it will be understood that a single detent for each spring would answer the purpose, and any simple mechanical contrivance by which the desired results are attained I consider within the scope of the invention.

The tension devices being single acting in their nature, the arms L M will be upwardly spring-pressed to an operative position from one direction only, but, being mounted upon a vertical pivot, when it is desired to reverse the direction of movement of the vehicle the outer ends of the arms willbe pulled downward by suitable line V until the contact devices are detached from the conductors,when, by means of the line V or its equivalent, the armscan beswung around upon their pivotinto reverse position, and then allowed to rise upward, under the influence of their tensionsprings, into engagement with the conductors. The vehicle is then in position to move in the reverse direction. A well insulated conductor 7' extends from the fork l, or other metallic part in electrical connection with the contact device 0, and is carried down one of the armsfor instance, the arm Mand at or near the base of said arm the conductor is led to a binding -post IV upon the base q. The binding-post is of course thoroughly insulated from said base, and is also in connection with the continuation of one side of the motor-circuit.

The arm L is provided with an insulated conductor r which is similarly led and fastened to a second binding-post IV which represents the other side of the motor-circuit. By placing the binding-posts WV W in the most convenient positions and allowing sufficient slack to the extremities of the movable conductors r 4 attached thereto, it will be evident that the arms may be reversed in position that is, placed toward either end of the caras desired, and this without injury or effect upon the slack ends of the conductors 0" r but it will be evident that the arms should always be moved from front to rear inthe same direction-that is, they should be moved back over the same course followed in previous movements-since with this arrangement continuous complete rotations of the said arms upon their vertical pivot would wind up and ultimately tear the slack ends of the conductors 0 0' from their bindingposts \V,-or otherwise rupture the circuit, whereas they may be moved back and forth upon or around the same side of the pivotal support as often as desired without injury.

The material of which the arms L M are constructed may vary greatly. In some instances I prefer to use wood; in others a light tapered metallic tube. Then again I have used a light steel truss-pole with excellent results in many cases. An essential feature of the present system is, however, that the arms be thoroughly and carefully insulated from their common support. I prefer to insulate the arms L M from their current-collecting devices I O, and to have the current from those points to the binding-posts XV \V, further insulation might be dispensed with.

1th single-acting tension-springs such as described it will be understood that when, either of the arms L M is turned backward out of its operative position a sufficient distance the tension of the spring is released. To replace a broken spring, it is therefore only necessary to remove a nut, linchpin, or other device on the extremity of the rod on, when the arm can be removed, and with it the spring. A new spring can readily be substituted and the parts replaced in position, when the mere act of returning the arm to its operative position imparts the desired tension to the spring. A less tension than that obtainable by these means may be secured by turning the arm back of its operative position a comparatively short distance, then loosening the parts, so as to disengage the ratchet or locking mechanism, then readjusting the parts, and moving the arm to operative position. Many varieties of spring might of course be substituted for that here shown.

Many changes and modifications may be made in the hereinbefore-described invention without departing from the spirit or scope thereof.

Having described my invention, what I claim, and desire to secure by Letters Patent, 1s-

1. A double suspended conductor system for electric railways,comprising positive and negative conductors following the line of each track, the conductors of one polarity over each track being arranged upon the inner sides thereof and electrically connected at intervals, the remaining conductors being parallel therewith but nearer to the outer sides of said tracks.

2. A double suspended conductor system for electric railways, comprising positive and negative supply-conductors following the line of each track, a branch extending from said main conductors, comprising metallic frogs in electrical connection with said main conductors, branch conductors connected to butinsulated from said frogs, and an upward pressure contact device having a plurality of independent insulated contacts adapted to engage the said supply-conductors.

Switching devices fora double suspended conductor system, comprising metallic frogs in contact with the main conductors, an insulated crossing for one of said conductors, a branch conductor extending from the frog of one of said conductors and engaging the crossing, but insulated therefrom, a continuation of the insulated b anch conductor, and an electrical connection uniting the insulated extremities thereof, and a branch conductor extending from and in electrical connection with the frog of the other main conductor.

4. Switching devices for a double suspended conductor system, comprising metallic frogs connected to the main conductors, branch conductors connected to but insulated from said frogs, a crossing for one of said main conductors to which one branch is electrically connected, a continuation of said branch eonductor and a frog upon the next adjacent main conductor to which the said continued branch is electrically connected, and a branch extending from the other main frog to but insulated from a crossing upon the next adjacent main conductor, a continuation of said second branch conductor and afrog upon the other main conductor to which said continuation is connected, and electrical connections between the insulated portions of the branch conductor.

5. A switch and crossing for a double system of duplex suspended conductors, comprisingmetallic frogs in electrical connection. with one set of main conductors, a branch conductor extending from one frog to and insulated from a crossing attached to conductors of the opposite polarity and connected thence but insulated therefrom by a conductor secured to a crossing of similar polarity, and a branch conductor extending from the other frog to an insulated crossing, and thence by a continuation of the branch conductor to a crossing of like polarity, thence to a crossing of opposite polarity from which it is insulated, thence by a continuation of the branch conductor, and an electrical connection between the insulated terminals of the branch conductor.

6. In a system of double suspended eonductors, a switch and crossing for a double duplex line comprising metallic frogs in. contact with the main conductors of one line, an insulated crossing for one of said conductors, a branch conductor extending from the frog of one of said conductors and engaging the crossing and insulated therefrom, a continuation of the insulated branch conductor, and an electrical connection uniting the insulated extremities thereof, a branch conductor extending from and in electrical connection with the frog of the other main conductor, and two sets of crossings connected with the main conductors of the other main line to which the branch conductors from the first-mentioned main line are connected and from which they may be continued, substantially as described.

7. In a duplex suspended system of conductors, a metallic frog in electrical connection with one of said conductors, a branch conductor connected thereto, and an insulating-section between the frog and the branch conductor, substantially as described.

8. A crossing-plate having a flat metallic surface, a central downward projection for guiding a grooved contact-wheel, and lateral flanges to prevent lateral displacement of the contact device.

9. The combination, with a metallic crossin g-plate, of a main conductor of one polarity connected thereto and ribs or pieces of insulating material also connected to said plate, and conductors of opposite polarity connected to the extremities of said insulating-ribs.

10. A crossing-plate for conductors of opposite polarity,'comprising a metallic plate secured to and in electrical connection with the main conductor, insulating-sections secured at opposite ends of the plate, and conductors of opposite polarity secured to the extremities of said insulated sections, substantially as described.

11. A crossing-plate comprising a metallic surface to which the main conductor may be attached, insulating-sections extending from each end thereof and connected to terminals of conductors of opposite polarity, a crossingplate comprising a metallic surface, a central downward projection for guiding a grooved contact-wheel thereacross, and terminals extending from each end forconnection to their respective conductors, substantially as described.

12. The combination, with acrossing-plate, of a main conductor connected thereto for crossing atone direction, ribs composed in part of insulating material and connected to said crossing-platcs for attachment to conductors of opposite polarity for a crossing of another direction, and protecting-roofs extending over the insulated portions of the said insulating ribs, substantially as described.

13. In a system of suspended conductors, an insulating-section and conductors of opposite polarity connected to the extremities thereof, whereby the said section is adapted to convey the contact device between insulated and separated continuous conductors.

14. In a system of suspended conductors, an insulating section for connecting conductors of opposite polarity, having high ten sile strength and composed of a metallic body having an exterior insulating-surface.

15. In a system of suspended conductors, an insulating-section the lower or contact surface of which is discontinuous, substantially as described.

16. In a system of suspended conductors, an insulating-section uniting the extremities of conductors of opposite polarity and provided with a protecting roof or cover, substantially as described.

17. In a system of suspended conductors, an insulated section for uniting conductors of opposite polarity, having its lower edge made discontinuous by notches or serrations and provided with discontinuous metallic wearingsurface between the serrations, substantially as described.

18. In a double suspended system of electric-railway conductors, a contact device com.- prising a pair of independent upwardly spring-pressed arms each provided with a contact device at its outer extremity, both said arms being free to swing about a,vertical axis, separate insulated connections between the contact devices and a stationary support or base, and a slack and flexible portion between the fixed and movable parts of the said circuit-eonnections for permitting said arms to swing upon their vertical axis for reversing.

19. In a double suspended conductor system,the combination, with a suitable support mounted upon a car or other vehicle, of a pair of contact-carrying arms, vertical and transverse axes sustaining said arms in positions to swing freely about the vertical axis, tension-springs pressing said arms independently upward against suspended conductors, and separate flexible conductors extending bet-ween the contact devices carried by the arms and connected to fixed terminals of the motor-circuit.

20. In a double suspended conductor system,the combination of a pair of arms, vertical and transverse axes for said arms, upon which they are mounted at their lower ends, tension-springs for imparting an upward tendency to said arms independently, and self adjusting and locking connections between the inner ends of said springs and a support, whereby the tension of the springs may be adjusted by moving the arms away from their operative position. v

21. In a double suspended conductor system, the combination of a block Q, mounted upon a vertical pivot, transverse arms, contact 

